docs: def can_play_notes(self, notes):
          """Test if the notes lie within the range of the instrument.
  
          Return True if so, False otherwise.
          """
          if hasattr(notes, 'notes'):
              notes = notes.notes
          if type(notes) != list:
              notes = [notes]
          for n in notes:
              if not self.note_in_range(n):
                  return False
          return True